Mushroom Potpie

While this dish took a bit of time to prepare, it was worth the effort. My mushroom mixture made more than I planned filling up a 9x13 rather than an 8x8, so I had to roll out the top a little thinner than desired. It still turned out great but would be better with a "thicker" pastry top.

Olive Oil
1 1/2 lbs mushrooms (I used a combo of cremini and button) halved, or quartered
4 carrots, cut into 1/2" pieces
3 celery stalks, sliced 1/4" thick
1 medium onion, chopped
1/2 tsp dried thyme
Salt and Pepper
1/3 c all-purpose
1 1/2 c vegetable broth
1 c frozen peas
1 sheet puff pastry, thawed (most are vegan, just check ingredients list)

Heat oven to 400. Heat 2 TBSP oil in large skillet over med-high heat. Add the mushrooms, carrots, celery, onion, thyme, 1/2 tsp salt, and 1/4 tsp pepper. Cook, stirring occasionally, until the vegetables are tender, 12-15 minutes. Add the flour and cook, stirring, for 30 seconds. Add the broth and peas; bring to a boil.
Transfer the mushroom mixture to an 8x8 baking dish. Lay the pastry on top and cut several vents in it. Bake until the crust is golden 20-25 minutes (place the dish on a rimmed baking sheet incase of overflow). Let rest 15 minutes before serving.